Non-cellulose fibers are useful in a variety of technologies. For example, glass fibers are used as reinforcements in polymer matrices to form glass fiber reinforced plastics or composites. Glass fibers have been used in the form of continuous or chopped filaments, strands, rovings, woven fabrics, non-woven fabrics, meshes, and scrims to reinforce polymers.
Glass fibers are commonly used as reinforcements in polymer matrices to form glass fiber reinforced plastics or composites because they provide dimensional stability as they do not shrink or stretch in response to changing atmospheric conditions. In addition, glass fibers have high tensile strength, heat resistance, moisture resistance, and high thermal conductivity.
Typically, glass fibers are formed by attenuating streams of a molten glass material from a bushing or orifice. An aqueous sizing composition containing a film forming polymer, a coupling agent, and a lubricant is typically applied to the fibers after they are drawn from the bushing to protect the fibers from breakage during subsequent processing and to improve the compatibility of the fibers with the bulk matrix resins that are to be reinforced. After the sizing composition has been applied, the sized fibers may be gathered into separate strands and wound to produce a glass fiber package. The glass fiber package may then be heated to remove water and deposit the size as a residue lightly coating the surface of the glass fiber.
The toughened film forming agents of the invention may be used with fibers other than glass. Exemplary of such fibers are carbon, graphite, basalt, boron, polyamide and the like. It would be desirable in the art of preparing and using glass fiber compositions to employ glass fibers with improved sizing.